How You Know You Have ItHypothermia: How You Know You Have It

Symptoms of hypothermia range from the hardly noticeable to the announcement of your death.

The First Signs

A runny nose is the mildest symptom. Lungs need the air you inhale to be humid. Cold air is nearly dry. When you inhale cold air, your body adds water vapor to it. Some of that comes out of your nose. When you’re mouth-breathing, you may not notice, but with your nose you’ll notice. It’s colorless, but if you’re wondering if you might be sick, go into a warm room and clear your nose. In general: If, after that, your nose runs again, you’re sick. If your nose stops running and you have no other symptom, you’re fine.

Skin redness, maybe. Even if redness is not visible, your skin’s blood vessels are expanding (doctors call it dilating), so they’ll carry more blood and warm your skin. No big deal, by itself.

More urination, especially if the total of everything you drank did not increase.

Shivering, the regular kind. It’s in short bursts. Your large muscles, especially in your chest, are trying to heat your blood up. Do something. You can forget the milder symptoms, but shivers are warning you.

More Serious

Pain in your feet or hands. Stumbling. Lagging. Losing fine coordination. Irritability. Amnesia of what happened just before a problem. Losing your fine-motor coordination is not evident if you’re just walking, but if you can’t get something into a small hole and usually you can, that’s telling you something. The type of amnesia is retrograde amnesia.

Not noticing companions’ hypothermia is common during hypothermia. They don’t notice it in you, either. You get still colder. Oops. Denial is not proof but happens, so consider objective facts. If you’re wearing only an undershirt and it’s just twelve degrees for more than a minute or two, declare yourself hypothermic. Scram.

If walking needs help, if standing needs help, that’s bad news.

Drowsiness. Slurred speech. Confusion. These are additional symptoms of hypothermia, according to a northern large city’s health department. However, these are also symptoms of other conditions, like, maybe, stroke. If a stroke happened, emergency treatment has to rush, even without cold weather. It’s usually best to call for medical help, and, if hypothermia may also be present, to treat that, too, like with clothing or relocation to a warm place, while you wait for other medical attention to arrive. Be sure where you relocate to will be obvious to the coming medical people. I wish diseases were easier to figure out, sometimes, but that’s life. Don’t panic. Look at what you can see and just do the best you can.

Forgetting. Slow in thinking, especially in being slow to figure out how you’re going to save yourself. Irrational, not creativity but simply your brain losing it.

If you get shocked with cold water, like by taking a dip in a winter ocean, your heart will probably race and you’ll likely gasp for air. If you can’t control that, you’ll likely hyperventilate. Before your core temperature drops, your skin temperature will drop quickly, as skin blood vessels shrink to conserve blood for your core organs. You might tingle and get numb. “Five minutes after being immersed in cold water, most people can’t put a key in a lock, [Columbia University Medical Center emergency physician Dr. Christopher] Tedeschi sa[id]”, as reported on .

Hair stands on end, especially skin hair. (Probably long hair or hair with grease is too heavy for this.) The skin forms goose bumps to make short hairs stand up and this holds air steady, probably by increasing the surface area to which air can attach itself. I don’t know how serious this is as a symptom compared to other symptoms.

If you have a medical thermometer that’s liquid-filled, not battery-powered, and that goes low enough, try it. If the marks on the thermometer don’t go low enough, don’t estimate it. Mine goes down only to 95.2 degrees Fahrenheit, but maybe yours measures further down. Normal temperature under the tongue is 98.6 degrees F. If the body temperature is less than 95 degrees F., that’s hypothermia. If your thermometer counts in Celsius or centigrade (C.), the equivalent is under 35 degrees C. If it’s under 86 degrees F. (30 degrees C.), that’s severe hypothermia. That’s an alarm. If it’s below the low 70s F. (low 20s C.), that’s usually in a corpse. But, usually, taking a body temperature is not practical. During recovery and in mild cases, no one needs it. In severe cases, people clamp their jaws, while an armpit or anal reading often forces exposure to cold, and an anal (rectal) reading may require turning the person over and risking breaking the heartbeat rhythm, maybe killing the patient. Use the time for warming, shelter, getting help, and everything else.

The Dead End Road

Deep shivering is nonstop. You’re in danger. Add clothes or enter a warm building, car, or truck, maybe even at the risk of getting arrested or beaten up. (That risk is a good reason to plan ahead, so you’ll stay warm without a felony or broken bones. There may be an ancient legal common-law defense about doing no more than you need in order to stay alive, but I’m no lawyer.) Or jam thick newspapers under your shirt. Or get a hug, even if the other person is an annoying nut. Get away from the wind. If you’re swimming, get out; unless it’s very windy and there’s little water current, even open air is safer, because it’s less conductive. (While death in cold water is usually due to drowning, hypothermia is still a disaster and is next in line to kill you.)

Deep shivering is a lot like what you get from an infection or the dietary problem called hypoglycemia (there’s general information on being hypoglycemic), but it’s not from those. You can tell by the circumstances. You didn’t have the brief shivers before. Infection-caused chills will shake your whole body, teeth make noise, and lips and nails go dark. Hypoglycemic shivers follow low food intake and exertion out of proportion to your ability and your food consumption. But if you’re shivering because the environment is cold, the shivering is mainly in your chest, because your chest muscles have to warm you up, you’ve had adequate food, and your exertions are within your abilities. If you’re not sure which it is, you can safely treat it as both, at least as hypothermia and treating the other possibility short of prescription medicines until a doctor makes a decision.

A hot plate, campfire, or stove could kill you. Your judgment is already impaired. You’re likelier to let an accident happen. The fire goes out of control. You die. A bunch of people die, and they won’t have any feelings about what you did, because they’ll be dead.

If you must build a fire to survive, be twice as careful, step by step. Or plan ahead, with clothing.

The end of shivering, if you’re still frozen, is even more dangerous. You’re about to die. Your body has already given up trying to heat enough blood. Your energy is too low. Take any help you can from any person, animal, or tree.

Warming up, but only too little. Maybe you go unconscious. Breathing becomes imperceptible. The pulse fades to imperceptible. That may be a coma, which may come with red and purple on the lower side of the body, from blood that’s not circulating. The comatose body may even be stiff. A coma may mean heart failure. Either way, you die. If you don’t die yet, you, or anyone in a coma (responding to nothing), needs gentle handling, so the heart doesn’t lose its rhythm and kill the patient.

The last stage was deduced from people who fell into cracks in glaciers. They could not be reached or rescued, never mind being seen by a doctor, but they were seen by their travel companions who couldn’t save them. People in the cracks (crevasses), before they went unconscious or comatose, were seen taking their coats off. This made no sense, so other people thought maybe the extreme cold made them delirious, made their brains confused. But a more recent thought is that the blood vessels in their skin, the capillaries, had enlarged, so more blood was flowing in their skin, and they felt warmer. Unfortunately, it’s not enough, and more blood in the skin means less in vital organs. That’s the same effect you’d get from drinking alcohol. It’s not enough warmth. So you breathe your last anyway. And, you’ll be pleased to know, it’s legitimate to leave you for dead even if you’re not really, and you’re helpless, too, and will likely die if alone. Hope you don’t mind. It’s often legal and sometimes smart. Rescuers usually need not jeopardize their own safety, or their own lives, just to save yours, if they didn’t contribute to your problem. You’re on your own, even when you have company. Preparation is up to you.

Plan ahead instead.

Hypothermia ultimately causes shivering, deep shivering, and, then, no longer shivering, which is when you’re about to die.

Websites of Interest

These websites have some interesting content, although I disagree with some of it:


Hiking organizations:

General retailers of outdoor products:

General information: